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How Filters Work

Ultraviolet or “UV” filters block some UV light from entering the camera lens. In outdoor photographs UV light increase the effect of atmospheric haze making distant subjects, such as mountains, in scenic photos less sharp. Be removing some of the UV light it reduces some atmospheric haze yielding clearer scenic photos.

Most people also us UV filters to protect their lens. Lenses can be expensive and so can repairing them if they get damaged. These filters provide an excellent first line of defense for the front element of the lens. High-quality UV filters can remain on the lens at all times as they have no effect on indoor photos and do not reduce the amount of visible light entering the lens.

UV filter (before)

UV filter (after)

A UV filter has glass that is specially formulated to absorb UV light at a certain wavelength and lower.

UV light that is not blocked by the earth’s atmosphere has wavelengths beginning at 315nm and going up to the visible violet light at the 400nm upper end of the visible spectrum. This light is commonly known as UV-A and not only is it bad for your eyes its bad for your photography. The visible light spectrum runs between 400mn violet and 700nm red. Even though UV light cannon be seen by the human eye it can have a negative impact on photos.
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Circular Polarizer filter (before)

Circular Polarizer filter (after)

When you here the word “Polarized” many negative things come to mind, well it’s the same in photography polarized light is something you don’t want and a Hoya Circular Polarizer filter can improve your photography.

Circular Polarizer filter (before)

Circular Polarizer filter (after)

Circular polarizing filters allow photographers to achieve creative, in-camera, effects not possible after the image is created. A polarizing filter simply filters out unwanted reflections from non-metallic surfaces such as water and glass in addition to light reflecting off moisture and pollution in the atmosphere. By rotating the filter you can select just the right amount of filtration needed to achieve the creative effect. This results in bluer skies, greener leaves, reduced or eliminated reflections, and greater clarity in your final image.

Circular Polarizer filter (before)

Circular Polarizer filter (after)

Polarized light is light who’s rays have been scattered due to pollution, moisture in the atmosphere and reflection. A circular polarizer filter only allows light rays that are traveling in one direction to enter the lens. This is how the Circular polarizer works it’s magic.
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Wonder how photographers get flowing water to look like a stream of fog? They use a strong Neutral Density (ND for short). The easiest explanation for what an ND filter does is reduce the amount of light entering your camera by set amounts. ND filters are dark with no color to them at all, hence the “Neutral” name.

Neutral Density filter (before)

Neutral Density filter (after)

The filter can be used in a variety of situations to create effects that are simply not possible to get any other way.

The best way to get these dreamy blurred motion effects is to use a strong neutral density filter like the Hoya SOLAS IRND 3.0. This dark filter reduces the amount of light entering the lens by a full 10 stops. In real world terms that means if on a sunny day the camera shows an exposure of 1/250 of a second shutter speed and an F/8 aperture, the IRND 3.0 will reduce the shutter speed 10 stops so with the same F/8 aperture the shutter speed would be 2 full seconds!

In darker situations, such as a stream in a forest on a cloudy day, shutter speeds as slow as 30 seconds can be obtained!

Neutral Density filter (before)

Neutral Density filter (after)

Always use a tripod when using strong ND filters to get long exposures so only the motion is blurred, not the things that are not moving!

Some will say that you can always stop down to a very small aperture such as F/16 or F/22 but keep in mind that most lenses will not be as sharp due to refraction issues at these small apertures. So unless you need the depth of field for an effect, apertures smaller than F/11 are not recommended for most lenses.
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Infrared, Exploring the World Beyond Visible Light

Infrared filter (before)

Infrared filter (after)

Ever wonder how to get those otherworldly effects where leaves are white in black & white photos instead of gray? An Infrared filter is the key. These filters are specifically designed to block visible light and only allow infrared light to pass through into the lens and camera.

Infrared filter (before)

Infrared filter (after)

Infrared photography yields very interesting, sometimes stunning, and creative results as objects in a scene can reflect infrared light very differently than normal light. A prime example is foliage. Leaves reflect a good mount of visible light but they reflect even more infrared light which is why they appear brighter in color infrared or while in black & white.
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